A solar minute was a unit of time measurement employed by the Federation in the 2260s.
History and specifics[]
In 2266, on the planet Beta II, a USS Enterprise landing party split up to search for ore deposits and agreed to rendezvous back in "thirty solar minutes." (TOS comic: "The Enterprise Mutiny")
In 2268, Montgomery Scott decided that they Enterprise would depart for the Sigma Quadrant if they did not locate Captain James T. Kirk within "thirty solar minutes." (TOS comic: "Day of the Inquisitors")
- No explanation has been provided as to the length of a solar minute.